Transmembrane delivery of different drugs includes transdermal, rectal, intranasal and intravaginal delivery. All these routes have mucous membranes which are a biological barrier in the delivery of exogenous drugs.
Transdermal administration is relatively easy and convenient as compared with oral administration and administration by injection and may also be advantageous in terms of duration of the effect and reduction of expression of the side effects, which also make transdermal administration an excellent administration method. However, in order to permeate the active ingredient into the body by transdermal administration, the active ingredient is to be penetrated through the skin which constitutes a primary barrier of the living body and its bioavailability (the amount of the drug absorbed within a blood flow) is inherently relatively low. Penetration enhancers are therefore needed to boost penetration of a biological membrane for delivery of injected substances utilizing transdermal administration.
To achieve bioavailability of active ingredients being transdermally administered, it has been shown that 1.2-propylene glycol, dipropylene glycol, hexylene glycol, isoparaffin, sodium laurylsulfate, ethylene oxide adducts of lauryl alcohol, fatty acids, ethyl alcohol, polyethylene glycol fatty acid esters, glycerol, polyoxyethylene sorbitan fatty acid esters, propyl carbonate, sodium pyrrolidonecarboxylate, urea, lactic acid, sodium lactate, lecithin, dimethyl sulfoxide, pyrrolidonecarboxylate, nicotinate, N-methylproline ester, amine oxide and other ingredients are prepared for external application as a transdermal absorption enhancer. Most existing transdermal enhancers are synthetic compounds that are considered foreign by a person's body and are not received relatively well.
In view of the foregoing, there is a need for a transmembrane penetration enhancer that is not considered foreign by a person's body and is received relatively well.
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